This invention relates to a door lock device for motor vehicles which can automatically operate a door in an incompletely closed (half-latch) position to a completely closed (full-latch) position.
The completely closed (full-latch) condition of a door of a vehicle can be obtained by engaging a striker which constitutes a body-side member of the vehicle with a latch which constitutes a portion of a door lock device provided on a back door or a side door. As shown in FIG. 8, the latch 1 is disposed rotatably about a pin 2 and is always forcibly directed in one direction by receiving a biasing force of a spring 3. The latch 1 includes an engaging groove 5 which receives a striker 4, a first pawl receiving portion 6 which is formed on the periphery of the latch 1 and establishes the door completely closed (full-latch) condition, and a second pawl receiving portion 7 which establishes the door incompletely closed (half-latch) condition. A protrusion 9 of a pawl 8 is engageable with one of both the pawl portions 6, 7.
The pawl 8 is rotatable about a pin 9xe2x80x2 which works as the center of rotation and the pawl 8 is always forcibly rotated in a direction toward the latch 1 by means of a spring 10. The pawl 8 is movable in the counter-clockwise direction corresponding to the movement of a pin 11 of a lift lever which belongs to an open system of a door lock device.
In the door opened condition or position, the engaging groove 5 is rotated in the right direction as seen in FIG. 8 and the protrusion 9 of the pawl 8 comes into contact with an outer peripheral surface 12 of the latch 1. Upon the door closing manipulation, the striker 4 enters the inside of the engaging groove 5 and forcibly rotates the latch 1 in the counter-clockwise direction and hence, the protrusion 9 is engaged with the second pawl receiving portion 7 to establish the incompletely closed (half-latch) condition, that is, the incompletely latched condition of the door. Upon the further door closing manipulation, the protrusion 9 is engaged with the first pawl receiving portion 6 so as to establish the completely closed (full-latch) condition, that is, the completely latched condition (condition shown in FIG. 8).
In the above-mentioned door closing manipulation, when the manipulation force is weak or the like, a case that the door closing manipulation ends with the protrusion 9 of the pawl 8 held in the incompletely closed condition in which the protrusion 9 of the pawl 8 is engaged with the second pawl receiving portion 7 may arise. Then, the door in the incompletely closed (half-latch) condition is automatically shifted to the completely closed (full-latch) condition by means of a door closer mechanism.
Examples of this type of door closer are disclosed in Japanese Patent Laid-Open Publication No. 96079/1990, Japanese Patent Laid-Open Publication No. 50045/1994 or Japanese Patent Publication No. 2816804/1999.
In the conventional door closer device, at least three switches consisting of a half-latch detection switch, an overlock (full-latch) detection switch and an initial position detection switch are arranged. In response to signals outputted from these switches, manipulations consisting of the start of pulling operation, the start of reverse operation to return a passive lever to the initial position, and the completion of the operation due to the detection of returning of the passive lever to the initial position and the stop of a motor are carried out.
However, the preparation and the mounting of three switches bring about drawbacks that the assembling operation becomes difficult and the device becomes large-sized.
Accordingly, it is an object of the present invention to provide a door lock device which can overcome the drawbacks of the above-mentioned prior art.
To overcome the above-mentioned drawbacks, the present invention adopts basic technical steps that a cam plate having a pair of signal generating portions is mounted on a motor output shaft and a cam switch having a contact member which comes into contact with each of these signal generating portions is combined with the cam plate.
To be more specific, the present invention provides a door lock device which includes a bracket which has a fixed relationship relative to a door panel, a door lock which includes a latch, a pawl and a latch lever which is fixedly secured to a rotary shaft of the latch, a passive lever which is rotatably supported relative to the bracket and includes a free end portion which is capable of coming into contact with the latch lever, a drive source which is retained by the bracket and mounts a cam plate on an output shaft thereof and is interlocked with the passive lever, a cam switch which has a contact member coming into contact with the cam plate and has a fixed relationship relative to the bracket, and a half latch switch which detects a door incompletely (half) latched condition of a latch which constitutes a door lock, wherein the cam plate includes a motor stop signal generating portion and a motor reverse rotation signal generating portion.
Upon the normal rotation of the motor, the passive lever is rotated by way of the cam plate to establish the door completely (fully) latched condition and simultaneously the signal generating portion of the cam plate outputs a signal to make the motor rotated in the reverse direction so as to return the passive lever to the initial position. Accordingly, two signals are outputted with one cam plate so that at least one switch can be eliminated.
These and other objects and advantages of the present invention will become further apparent from the following detailed explanation.